Jason's neighborhood has an emergency water tank with a capacity of 10,500 L. How many mL of water does the tank hold?

Hello!

mL stands for milliliters. As usual, the prefix "milli" means "one thousandth" of the unit following it.

Any quantity contains one thousand of its thousandths. So does liter,  1 L = 1000 mL. Therefore x liters = 1000x mL. In our case x=10,500, so 1000x = 10,500,000 (add three zeros at the end).

It is possible also to express this number in the standard form to reduce the number of zeros in the expression: 10,500,100 = `1.05*10^7.`

So the answer: 10,500 L = 10,500,000 mL = `1.05*10^7` mL.